Run time error 1004, in my macro loop - excel

Question

'Declare Variables
Dim rng As Range
Dim AmQ As Worksheet, UpIss As Worksheet, QuMa As Worksheet
'Set your sheet names into variables for easier referencing
Set AmQ = Sheets("AMEND QUOTE")
Set UpIss = Sheets("UPISSUE")
For i = 7 To 57 '7 = Column H, 8 = Column G, etc.
'Set the address of the found value to the rng variable
Set rng = UpIss.Cells.Find(What:=AmQ.Cells(4, i).Value, After:=ActiveCell, LookIn:=xlValues, _
LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
MatchCase:=False, SearchFormat:=False)
If Not rng Is Nothing Then 'CHECK IF THE SEARCH TERM (FROM QUOTE SHEET) WAS FOUND IN THE TARGET SHEET (ESTIMATE)
If Not rng = "" Then 'CHECK IF THE SEARCH TERM WAS A ZERO LENGTH STRING
rng.Offset(1, 0).Select
Range(ActiveCell, ActiveCell.Offset(14, 0)).Copy 'Copy the cell 41 rows down and 3 columns across
'QuMa.Cells(4, i).Offset(14, 0).PasteSpecial Paste:=xlPasteValues 'Paste into the cell 14 rows below the original search term in the QUOTE sheet
Sheets("QUOTE MASTER").Select
Range("C5000").End(xlUp).Select
ActiveCell.Offset(1, 0).Select
'Copy Formats
Selection.PasteSpecial Paste:=xlPasteFormats, Operation:=xlNone, _
SkipBlanks:=False, Transpose:=True
'Copy Values
Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
:=False, Transpose:=True
'Autofit
Columns("C:Q").EntireColumn.AutoFit
Application.CutCopyMode = False
ElseIf rng = "" Then 'EXIT SUB IF SEARCH TERM WAS A ZERO LENGTH STRING
'MsgBox "Work is Done"
Exit Sub
End If
ElseIf rng Is Nothing Then 'EXIT SUB IF SEARCH TERM WAS NOT FOUND IN THE TARGET SHEET
'MsgBox "Work is Done"
Exit Sub
End If
Set rng = Nothing
Next i 'Move to the next column across and loop
This is where I am getting my error:
rng.Offset(1, 0).Select
Range(ActiveCell, ActiveCell.Offset(14, 0)).Copy
not able to copy in the loop.